[lkml]   [2019]   [Jun]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    Patch in this message
    Subject[PATCH 4.19 106/118] pwm: tiehrpwm: Update shadow register for disabling PWMs
    [ Upstream commit b00ef53053191d3025c15e8041699f8c9d132daf ]

    It must be made sure that immediate mode is not already set, when
    modifying shadow register value in ehrpwm_pwm_disable(). Otherwise
    modifications to the action-qualifier continuous S/W force
    register(AQSFRC) will be done in the active register.
    This may happen when both channels are being disabled. In this case,
    only the first channel state will be recorded as disabled in the shadow
    register. Later, when enabling the first channel again, the second
    channel would be enabled as well. Setting RLDCSF to zero, first, ensures
    that the shadow register is updated as desired.

    Fixes: 38dabd91ff0b ("pwm: tiehrpwm: Fix disabling of output of PWMs")
    Signed-off-by: Christoph Vogtländer <>
    [ Improve commit message]
    Signed-off-by: Vignesh Raghavendra <>
    Signed-off-by: Thierry Reding <>
    Signed-off-by: Sasha Levin <>
    drivers/pwm/pwm-tiehrpwm.c | 2 ++
    1 file changed, 2 insertions(+)

    diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
    index f7b8a86fa5c5..ad4a40c0f27c 100644
    --- a/drivers/pwm/pwm-tiehrpwm.c
    +++ b/drivers/pwm/pwm-tiehrpwm.c
    @@ -382,6 +382,8 @@ static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)

    /* Update shadow register first before modifying active register */
    + ehrpwm_modify(pc->mmio_base, AQSFRC, AQSFRC_RLDCSF_MASK,
    ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
    * Changes to immediate action on Action Qualifier. This puts

     \ /
      Last update: 2019-06-13 18:11    [W:2.209 / U:0.020 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site